Higher Rate of Cervical HPV Found
By GAUTAM NAIK
Wall Street Journal
February 28, 2007
A U.S. study suggests that the prevalence of a sexually transmitted virus that can cause cervical cancer is greater than previous estimates had suggested. The data also indicate that the prevalence of the two main cancer-causing strains of the virus, for which there is a new vaccine made by Merck & Co., appears to be relatively low.
The second finding could play into a debate over Merck's vaccine, Gardasil, which protects against the human papillomavirus, the virus that causes most cervical-cancer cases. The Whitehouse, N.J., drug maker had aggressively lobbied states to pass laws requiring preteen girls to be vaccinated against cervical cancer, though it recently ended that effort. Still, bills being drafted in about 20 U.S. states would make Gardasil mandatory for preteen girls. Many parents, consumer advocates and conservative Christian groups oppose the idea.
The study appearing today in the Journal of the American Medical Association looked at U.S. females aged 14 to 59. The combined prevalence of two high-risk strains of HPV, types 16 and 18, was about 2% in that population, which the paper called "relatively low," compared with other estimates. But it noted that those two strains are responsible for about 70% of cervical cancers world-wide, and Gardasil protects against both.
Richard Haupt, executive director of medical affairs in Merck's vaccine division, said he agreed that the virus strains that Gardasil protects against are relatively rare, but argued that the vaccine was still a potent weapon, because the 16 and 18 strains were responsible for most cervical cancers. "It indicates that there are many women who will benefit from being protected" by Gardasil, he said. Approved by the government last year, the vaccine also protects against genital warts, a low-risk infection.
Overall, the JAMA study found that the prevalence of HPV was 26.8% among U.S. females in the 14-to-59 age bracket it examined, which equates to about 24.9 million women. Prevalence of the four strains of HPV that Gardasil protects against -- including the more dangerous types 16 and 18 -- was 3.4%, corresponding to about 3.1 million females.
The highest prevalence of HPV was found in females aged 20 to 24 years. In the age group 14 to 24, the prevalence was 33.8%, corresponding to 7.5 million females with HPV infection. A previous estimate had indicated that the prevalence in that age group was 4.6 million.
The newer, higher figure "doesn't indicate a trend" of rising infections, said Eileen Dunne, a medical epidemiologist at the U.S. Centers for Disease Control and Prevention in Atlanta, and lead author of the paper. Instead, she said, the difference in the figures "is based on a better method of looking at this question."
The study has limitations. The prevalence data doesn't capture cases of women who were infected by HPV in the past but have since been cleared of the virus. (About 90% of infections clear within two years.)
Meanwhile, two large clinical trials studying Gardasil will end earlier than planned because of the product's effectiveness, said Sanofi Pasteur MSD, a joint venture of drug makers Sanofi-Aventis of France and Merck.
Article link: http://online.wsj.com/article/SB117260163395420928.html?mod=home_whats_news_us
Senator Tom Coburn
Subcommittee on Federal Financial Management, Government Information, and International Security
340 Dirksen Senate Office Building Washington, DC 20510
Phone: 202-224-2254 Fax: 202-228-3796
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